Amphibious airplane



FIG. 1 is a front perspective view of an Amphibious Airplane showing my new design;

FIG. 2 is a side view thereof;

FIG. 3 is a front elevation thereof;

FIG. 4 is a rear elevation thereof; and

FIG. 5 is a bottom plan view of the airplane. 

The ornamental design for an amphibious airplane, as shown. 